Tuesday, October 12, 2010

Golden Age of Handbuilt Bicycles by Jan Heine

I recently received as a generous gift the Golden Age of Handbuilt Bicycles by Jan Heine with photography by Jean-Pierre Praderes. Jan is the editor of Bicycle Quarterly, to which I've recently subscribed, and Jean-Pierre clearly has a real talent for photography. The two combine to put together an incredible book.

This book only reinforces the impression I'd already gotten from Jan's writing in Bicycle Quarterly: that randonneur bikes, rather than being the over-weight, poorly handling, sluggish beasts I'd always assumed, are actually fairly competitive machines which are actually far better suited to the sort of riding that most avid cyclists do than the typical racing bike sold in the vast majority of high-end shops in the United States or, for that matter, anywhere else I've seen high-end shops.

And the bikes described in this book are nothing short of high-end. The Technical Trials which became popular in France in from the 1930's until World War II provided a competitive arena for the optimization of light-weight, high-performance bikes sufficiently robust to survive the stresses of an unsupported race over multiple days of in excess of a hundred kilometers per day. And not only finishing the race was enough: the bike had to do so without mechanical failure or cosmetic damage or points were deducted. Some of these bikes even approached the present UCI weight limit of 6.8 kg, even with fenders and front racks.

In contrast, the professional racers who are the paradigms for today's top end bicycles are able to treat their bikes as fully disposable. Problems on the road typically cost the rider tens of seconds only, as a team car pulls up to replace the broken machine virtually instantly. It hardly seems relevant for the average rider who expects a bike to, above all else, not fail during long rides on remote roads.

These past few months one of my favorite ride activities has been SF2G, a central forum for people to organize bike commutes from San Francisco down the Peninsula to Google in Mountain View. Around half the riders in a typical ride work at Google, the other half like me either split off a bit early or continue on after the group reaches its primary destination. SF2G is a fantastic way to start the day: I always feel exceptionally productive and days I join one of the rides.

The typical SF2G rider is a on a road racing bike, carrying work clothes, laptops, and I'm not sure what else in backpacks. I really prefer to minimize the amount I carry on my back, so this (on which I am typing now) 7 lb Thinkpad simply does not make the cut. If I need the laptop, I take the train, otherwise I transfer files via SSH to a desktop at work and do without, reading on my train ride back north at the end of the day rather than my usual practice of working on the Thinkpad. Not so bad, really. But it would be nice to have the freedom to carry more between work and home.

Usually those who don't like a backpack use a rear pannier instead. But loaded rear panniers affect a bike's handling. The center-of-mass is shifted back, increasing the separation between the center of mass and the front tire. Since bikes lack all-wheel-steering, the front wheel is responsible for shifting the bike's orientation. Less distance between the front wheel and the center of mass translates to quicker steering. So for better handling, putting the weight on the front rather than the rear makes sense.

For this you need a front rack. A single pannier on the front will unbalance the front wheel, while two panniers is likely overkill. For light loads, a front rack keeps the front balanced. But if you simply load a front rack on a bike designed to be used without a rack, the handling will be affected. The additional weight on the front wheel will make the wheel want to flop over. The tendency of a wheel to flop depends on the bike's trail and on the head tube angle. So if you are going to design a bike to take a front rack, you want the trail to be relatively small.

Unfortunately most touring bikes are designed with a lot of trail to be stable when carrying a lot of gear front and rear. A touring bike isn't supposed to turn quickly: that's not the priority for the intended application. But for SF2G, on the other hand, riders like to challenge each other going for Strava segments and generally putting the hurt on each other: all in a good morning's fun.

Another issue with SF2G is in the SF Bay area it tends to rain a significant amount from November to April. Since I for one don't like getting soaking wet on a cool morning, I tend to stay away from the ride during days when there's a chance of rain along the way. It's well known that fenders help enormously in keeping a rider dry. But detachable fenders tend to get knocked out of alignment, rubbing the tires, and so it's tempting to leave them off unless absolutely necessary. Far better would be integrated fenders, designed into the bike. But everyone knows bikes with fenders are clunky, heavy, and slow.

This was my perception before Bicycle Quarterly and the Golden Age of Handbuilt Bicycles. If you want to go slow, load up your touring bike with panniers. But for speed, the unencumbered racing bike was the only option. Randonneur bikes, with their racks and fenders, were a close derivative of touring bikes. Sure, okay if you were interested in squeaking under the 90-hour limit at Paris-Brest-Paris. But if you had any interest in getting someplace quickly, forget about it.

My view was reinforced by my experience putting fatter tires on my bike, such as 25 mm or 28 mm. 28 mm tires always seem to result in sluggish handling and reduced cross-wind stability. But tire size affects the trail, as well as how the trail is affected by bike lean and steering angle. So if you want a bike with fatter tires, you need to design the geometry with fat tires in mind. What I didn't realize until I read Bicycle Quarterly that there's no fundamental issue with fatter tires and steering: if the bike is designed to accommodate the "pneumatic trail" of the tires, it can still ride perfectly well even with tires 40 mm wide (which would typically be on smaller-radius wheels than 23 mm tires).

But all you have to do is browse the photos and caption in this book (the text is very worth reading as well) to have this sort of view dispelled. There's photos of riders setting records in Paris-Brest-Paris (Maurice Macauiére and Robert Demilly) the Puy de Dome Hillclimb (Lylee Herse) on bikes with fenders and front racks. Randonnées (or "brevets"), in France, were and continue to be competitive events, at least among the fastest riders. The bikes they ride have little in common with lumbering touring machines. They're designed to be nimble, light, and fast.

Yet the speed isn't without compromise. Given the long distances and lack of support vehicles in randonnées, it's important riders don't get soaking wet, so a few hundred grams invested in fenders is more than worthwhile. And the roads are often in less-than-ideal condition: to avoid beating up the rider, the bikes have fatter tires than road-racing-specific bikes, for example 32 mm up to even 45 mm. And since the longer brevets extend into the night, lighting is required, and is often integral to the design of the bike, for example with internal wiring to protect the electrical wires. A few hundred grams of extra weight are small consideration relative to reducing rider trauma during a ride which may extend for up to several days with only a handful of hours rest.

This sort of bike would also be perfect for SF2G, I realized. A front rack to carry work clothes, fenders in case of rain, and a bit more rubber in the tires to handle the sketchy pavement on Tunnel Ave, San Bruno, and countless other poorly maintained roads along the route, not to mention the completely unpaved approach to the Bridge to Nowhere.

But consider even my ride today. I went from Costanoa (south of Pescadero) to Davenport and back. There's a really good bakery in Davenport which sells some delicious whole wheat artichoke bread. But since I was on my Ritchey Breakaway, a racing bike, I really didn't have anywhere to carry even a single loaf of bread. Even a minimal rack, on the other hand, would have handled it trivially. Now if I want the bread I face a 25 mile car trip to and from the bakery, having already ridden there. A bit silly to take a `1000+ kg motor vehicle to get an 800 gram loaf of bread, when a 400 gram rack would have done the job.

So Jan's work, both his magazine and this excellent book, have somewhat opened my eyes to the world of lightweight, performance-oriented, randonneuring bikes. Really I think a lot more people would be better served with similar machines than the bikes far more popularly sold, modeled after pure racing machines of one sort or another. After all, how many of us drive racing cars or Moto Grand Prix motorcycles? In motor vehicles, we as a population choose all-around vehicles which do what we need to do. If bikes are to be more than toys, then it makes sense to choose them to be similarly useful.

1 comment:

On my last trip through Pescadero I solved the artichoke bread carting problem by eating the entire thing. In a civilized manner by stopping to scarf it down. Still bonked later on the Portola SP-Alpine climb though...